Adds JoinedUserActivity model to associate users to every activities they created

app/controllers/api/v1/activities_controller.rb

@@ -13,6 +13,10 @@ class Api::V1::ActivitiesController < ApplicationController
   def create
     activity = current_user.created_activities.build(activity_params)
     if activity.save
+      JoinedUserActivity.create!(
+        user_id: current_user.id,
+        activity_id: activity.id
+      )
       render json: activity, status: :created
     else
       render json: { errors: activity.errors }, status: :unprocessable_entity

app/models/activity.rb

@@ -1,6 +1,9 @@
 class Activity < ApplicationRecord
   belongs_to :author, class_name: "User"
   
+  has_one :joined_user_activities
+  has_one :user, :through => :joined_user_activities
+
   validates :name, presence: true
   validates :author, presence: true
 end

app/models/joined_user_activity.rb

@@ -0,0 +1,4 @@
+class JoinedUserActivity < ApplicationRecord
+  belongs_to :user
+  belongs_to :activity
+end

app/models/user.rb

@@ -5,5 +5,9 @@ class User < ApplicationRecord
   validates :password_digest, presence: true
 
   has_many :created_activities, foreign_key: 'author_id', class_name: 'Activity', dependent: :destroy
+
+  has_many :joined_user_activities
+  has_many :activities, :through => :joined_user_activities
+
   has_secure_password
 end

db/migrate/20210429184439_create_joined_user_activities.rb

@@ -0,0 +1,10 @@
+class CreateJoinedUserActivities < ActiveRecord::Migration[6.1]
+  def change
+    create_table :joined_user_activities do |t|
+      t.references :user
+      t.references :activity
+
+      t.timestamps
+    end
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2021_04_13_142821) do
+ActiveRecord::Schema.define(version: 2021_04_29_184439) do
 
   create_table "activities", force: :cascade do |t|
     t.string "name", null: false
@@ -23,6 +23,15 @@ ActiveRecord::Schema.define(version: 2021_04_13_142821) do
     t.index ["name"], name: "index_activities_on_name"
   end
 
+  create_table "joined_user_activities", force: :cascade do |t|
+    t.integer "user_id"
+    t.integer "activity_id"
+    t.datetime "created_at", precision: 6, null: false
+    t.datetime "updated_at", precision: 6, null: false
+    t.index ["activity_id"], name: "index_joined_user_activities_on_activity_id"
+    t.index ["user_id"], name: "index_joined_user_activities_on_user_id"
+  end
+
   create_table "users", force: :cascade do |t|
     t.string "email", null: false
     t.string "username", null: false

db/seeds.rb

@@ -2,11 +2,13 @@ User.delete_all
 User.reset_pk_sequence
 Activity.delete_all
 Activity.reset_pk_sequence
+JoinedUserActivity.delete_all
+JoinedUserActivity.reset_pk_sequence
 
 10.times do |i|
   name = Faker::Name.first_name.downcase
   user = User.create! username: "#{name}", email: "#{name}@email.com", password: "azerty"
-  puts "Created user ##{i} - #{user.username}"
+  puts "Created USER ##{i} - #{user.username}"
   
   2.times do
     activity = Activity.create!(
@@ -15,6 +17,12 @@ Activity.reset_pk_sequence
       description: Faker::Company.catch_phrase,
       author_id: user.id
     )
-    puts "Created activity \"#{activity.name}\" for #{activity.client}"
+    puts "Created ACTIVITY \"#{activity.name}\" for #{activity.client}"
+
+    joined_user_activity = JoinedUserActivity.create!(
+      user_id: user.id,
+      activity_id: activity.id
+    )
+    puts "Created ASSOCIATION ##{joined_user_activity.id}"
   end
 end

test/fixtures/joined_user_activities.yml

@@ -0,0 +1,11 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+# This model initially had no columns defined. If you add columns to the
+# model remove the '{}' from the fixture names and add the columns immediately
+# below each fixture, per the syntax in the comments below
+#
+one: {}
+# column: value
+#
+two: {}
+# column: value

test/models/joined_user_activity_test.rb

@@ -0,0 +1,7 @@
+require "test_helper"
+
+class JoinedUserActivityTest < ActiveSupport::TestCase
+  # test "the truth" do
+  #   assert true
+  # end
+end